Printing Star Plates

[Twignberry]

Since getting my FDM printer up and running, I'm realising just how many possible applications it has for making pyro tooling.

 

This is the latest, a 67 pin 6mm star plate

 

Sorry for the poor photos, its actually translucent flouro green which is cool because you can see the internal honeycomb structure.

 

http://i127.photobucket.com/albums/p132/rangaz/PLA%20star%20Plates/IMG_5228_zps5aapdnkh.jpg

 

http://i127.photobucket.com/albums/p132/rangaz/PLA%20star%20Plates/IMG_5230_zps7z35iwdc.jpg

 

http://i127.photobucket.com/albums/p132/rangaz/PLA%20star%20Plates/IMG_5231_zpsf4eh1cxp.jpg

 

It has tapered pins so 95% of the pin shafts are 5mm diameter and just the head is 6mm, preventing binding from composition stuck on the walls.

 

The two depth limiters are captured in the pin plate by small clips.

 

The material is PLA which is resistant to acetone (untested) and is quite strong but a little brittle so wont really hold up to a dead blow mallet. Hand pressing should be just fine though.

 

Obviously size is limited but even with a 25mm comet, you should still be able to fit in ~10 pins. It's probably more limited by max consolidation pressure.

 

The really exciting thing is that it could print all sorts of pin styles for cavity and crossette comets.

 

All that was done after picking it off the build plate was cleaning up the bores with a 6mm drill

[starxplor]

Is hand pressure enough for a star plate? With everything I have been reading lately, I was worried a mallet would not be strong enough to cause the stars to retain their form when ejected.

 

Let us know how the stars turn out when you get to use it?

[Twignberry]

I've found hand pressure to be fine on my 70 pin 10mm plate and a rather shoddy 7 pin 20mm. You just need to use a bit more water than those pressed with hydraulics. Still significantly less than cut stars though .

[stix]

Interesting post, and also the one regarding the visco machine.

 

What software is required to create the files - Is it particular to the machine or are there alternatives?

 

Cheers.

 

Just googled - looks like a lot of work, but still interested.

Edited September 4, 2015 by stix

[Bcorso85]

I think that's great. I'd be interested in one.

[dave321]

thats very interesting

 

do you plan on printing anymore

 

how will it stand up to light hydraulic / arbor press type pressing

 

 

where are you based?

[ddewees]

That's cool!

[Twignberry]

Thanks for the interest guys,

 

I'm from the land of koalas and kangaroos so shipping might be a killer but once I get some time, I'll knock up a few of different sizes (some 25mm crossettes too ) and put them through some testing to get a better idea of durability.

 

Stix, to answer your question. I'm using professional 3d CAD software to generate models. From the models I import them into a Slicing program (Slic3r), which breaks the model into layers and generates g-code paths. I can then print g-code direct from SD or connect my printer to a PC and use a host program such as pronterface (printrun).

 

The printer design is quite old from 2013, an open source prusa mendel i2. Its been slowly upgrading itself to greatly improve rigidity by printing better, stronger and more intricate parts with each iteration. Oh and I also put a mk8 makerbot extruder on it

[AAF]

for those interested in trying it
You can use goggle sketch up (free) to make models and export an STL the printer can read.
work in mm and add 100 to every measurement ( 2mm =200mm) and then down size by .01 using the scaling tool, also set the Circe sides to something like 200...

[wizard7611]

Very nice star plate!

Edited September 12, 2015 by wizard7611

[MrB]

Something that really is quite useful, is the ability to make square pumps, and star-plates. Square stars stack a lot better in cylinder shells for some odd reason...

I'm just thinking the pressures needed might be to high for the plastic..

B!

[stix]

Hi Twiggs, I've been thinking... I've got a couple of small projects where 3D printing the bulk of the object might be much easier than making it by hand. Also being able to reproduce it exactly the same again has benefits.

 

So I was wondering how strong and/or flexible the material is. As an example, compared to the standard wooden icy-pole (popsicle) stick. Snaps easy, bends etc. I would have to learn to use the software to create the files, and pay you to print them, but it may be worthwhile.

 

Cheers.

[dave321]

I had a 6mm star plate printed

 

used it once, placed in dishwasher to give it a good clean (65c)

 

came out all distorted and useless

 

just something to be aware of

 

maybe the wrong plastic was used ? I don't know the m.p.s of pcl or abs

Edited November 9, 2015 by dave321

[dusty56]

On Passfire Kyle has posted a set of star screen programs for 3D printing. I don't have a printer and I could not justify the cost just for the screens. But if I could print square holed plates that hold up to my press…Hm

[Twignberry]

Hahahaha, sorry about your star plate but it was likely PLA if that happened in the dishwasher. It tends to droop and distort even in a hot car as it has a glass temperature around 50 deg C. ABS goes muuuuch higher

 

Stix, As long as you keep PLA below 50deg C, without actual numbers in front of me, I would guess it has a similar rigidity to a popsicle but has significantly higher hardness and I guess a moderately greater yield/UTS. There's quite a number of places offering printing services these days. There's likely even a few nearby you

 

ABS is less rigid and yields lower than PLA but it tends to stretch alot more and absorbs impact much better.

 

Its amazing how handy a printer can be round the house. It's made tap wrenches, 3d textured text for some fancy invite cards, Hair straightener wall mounts, Food labels and countless little clips.

 

I was going to give the featured star plate away for another member to try out but we had a break-in the other week and among a butane blowtorch and cheap jewelry, they made off with my backpack which had the star plate in it . I'll be back on track in a few weeks though

[starxplor]

Hahahaha, sorry about your star plate but it was likely PLA if that happened in the dishwasher. It tends to droop and distort even in a hot car as it has a glass temperature around 50 deg C. ABS goes muuuuch higher

 

Stix, As long as you keep PLA below 50deg C, without actual numbers in front of me, I would guess it has a similar rigidity to a popsicle but has significantly higher hardness and I guess a moderately greater yield/UTS. There's quite a number of places offering printing services these days. There's likely even a few nearby you

 

ABS is less rigid and yields lower than PLA but it tends to stretch alot more and absorbs impact much better.

 

Its amazing how handy a printer can be round the house. It's made tap wrenches, 3d textured text for some fancy invite cards, Hair straightener wall mounts, Food labels and countless little clips.

 

I was going to give the featured star plate away for another member to try out but we had a break-in the other week and among a butane blowtorch and cheap jewelry, they made off with my backpack which had the star plate in it . I'll be back on track in a few weeks though

 

Once you have this tested and working, would you be distributing the design files? I have access to a printer at my local hackerspace and would be interested in giving it a try.

[stix]

... Its amazing how handy a printer can be round the house. It's made tap wrenches, 3d textured text for some fancy invite cards, Hair straightener wall mounts, Food labels and countless little clips.

 

I was going to give the featured star plate away for another member to try out but we had a break-in the other week and among a butane blowtorch and cheap jewelry, they made off with my backpack which had the star plate in it . I'll be back on track in a few weeks though

 

3D printing will change the world in a similar, but much more significant way, like "flat" paper printing is being surpassed by our everyday electronic devices. Best to accept it, embrace it, and make something of it.

 

Sorry to hear that you got your backpack knocked off. Jewelry is way over-rated anyway - shame about the star plate .

 

[EDIT] Designing and using the software to create things will be the harder part - and perhaps where money could be made.

Edited November 10, 2015 by stix

[taiwanluthiers]

I think if you wet parlon bound stars with just enough acetone to get a sandy (but not wet) mixture, you will be able to load the star mixture into the plate, pump it with moderate pressure, and it should dry rock hard. Can I ask if the printed star plate is flexible at all? I would think it should be as stiff as possible.

[Col]

I think a bit of flexibility may be good for a plastic starplate, better to bend than break

Edited December 11, 2015 by Col

[starxplor]

Being flexible is fine, on its own, but for actual use, you want even and consitant force across tehe entire surface of the plate. Usually, presses have some kind of nice and big base, but the part pressing down is smaller, a shaft of some kind. The goal of a firm sturdy plate is that force on the center of the plate evenly spreads and brings all pins down on the comp at the same pressure. If the plate bends at all, you would need an extra piece on top of the plate for the press to act on. This may be easy for some, but a small press may not have the clearance of a user may not have a thick enough piece of metal that is still small enough to fit in the press.

 

Basically, we need to know how the plates act in order to determine for each of us if it will work, but either way can be done with the right setup.

[schroedinger]

Well even if the plate is a bit flexible itself, that shouldn't mater. You can always add a 2nd metall plate on top of the plate to distribute force.

[Col]

Flexibility is a plus when the starplate wont fit in your press Here`s a 4mm "pinless" starplate (407 hole) which uses the force from 2 steel rollers to compress one line of stars at a time (18-19 per line). Takes 10-15 seconds to crank it through the rollers. Wouldnt be useful for big stars but it works great for churning out little `uns for cake inserts and cores for rolling.

 

 

 

[Sarge]

I have been given one these star plates by twignberry for testing.

I pumped a few plates of "Red Rubber" stars, bound with redgum.

Using methylated spirits to dampen the comp, I tried a few different consistencies. I was only using hand pressure on the plate for fear of breaking it on it's maiden voyage.

I have plans to try it at low pressures in my arbor press as well.

They stars turned out a little crumbly, but if I left them alone to dry after pumping they dried solid.

I will report back at a later date how the higher pressure pressing goes. I may well test this plate until it fails to see what it's limits are.

Sarge.

[Twignberry]

Thanks sarge, agreed the 6mm pins feel flimsy. Perhaps load 'em up, you might be pleasantly surprised. Worst case if you break it, I'm happy to knock up a similar sized 10mm plate.

 

If hand pressing, the moisture either needs to be increased or you just have to be gentle while the stars are wet. Depending on the comp (D1 particularly because I keep it super dry), I quite often get crumbly wet stars. They always dry rock hard though.

 

Here are my results with two new ones I've printed up

 

http://i127.photobucket.com/albums/p132/rangaz/PLA%20star%20Plates/IMG_5569_zpstlll4iy1.jpg

 

It's a 6 pin 20mm and a new crazy idea I have for can shells. The comp is a basic charcoal star and it has only just been wet enough to barely clump together.

 

http://i127.photobucket.com/albums/p132/rangaz/PLA%20star%20Plates/IMG_5570_zpszc9s8erq.jpg

 

http://i127.photobucket.com/albums/p132/rangaz/PLA%20star%20Plates/IMG_5571_zpsfttyac9t.jpg

 

http://i127.photobucket.com/albums/p132/rangaz/PLA%20star%20Plates/IMG_5573_zpsrr6carjr.jpg

 

http://i127.photobucket.com/albums/p132/rangaz/PLA%20star%20Plates/IMG_5574_zpsjufr5mvz.jpg

 

http://i127.photobucket.com/albums/p132/rangaz/PLA%20star%20Plates/IMG_5575_zpsvgiypjua.jpg

 

http://i127.photobucket.com/albums/p132/rangaz/PLA%20star%20Plates/IMG_5576_zpsducqpj3y.jpg

 

The stars were only hand pressed so just like sarges comments, they were a bit crumbly. The 20mm pins feel very solid and when I get a chance, I will press them properly to see how they hold up. Regardless, the stars still dried rock hard as usual, just had to be careful handling them wet.

 

The next plate is a crazy idea to optimise and simplify the filling of a can shell. This was just a test so I went with the easiest geometry to calculate in the software. In the final plate, dead space would be minimised.

 

http://i127.photobucket.com/albums/p132/rangaz/PLA%20star%20Plates/IMG_5578_zpsyzpgzpq5.jpg

 

The cutouts are drafted from one side so that the finished stars just pop out with almost no force. You pack it in from the larger side by hand and then trim as you would with a star plate.

 

http://i127.photobucket.com/albums/p132/rangaz/PLA%20star%20Plates/IMG_5579_zpsxlyccfts.jpg

 

Then just flip the plate over carefully, the stars just about fall out under their own weight.

 

This would definitely work better with the composition alot damper, almost like cut stars

 

http://i127.photobucket.com/albums/p132/rangaz/PLA%20star%20Plates/IMG_5580_zpswdwy5xnh.jpg

 

http://i127.photobucket.com/albums/p132/rangaz/PLA%20star%20Plates/IMG_5581_zps82yqui6y.jpg

 

It's cool, the draft means the edges don't smear as they are ejected and you can still see the lamination lines from the mould.

 

So what do you think? Insanity or a stroke of genius?

 

*edited to add the stars

 

http://i127.photobucket.com/albums/p132/rangaz/PLA%20star%20Plates/IMG_5577_zpsd3habqvw.jpg

Edited December 15, 2015 by Twignberry

[schroedinger]

I like how you made the mold for the cannister shell, perfect adaption of a discussion we had about 3/4 year ago here when talking about quadrant inserts.